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1.
Investigatory behavior with novel, inanimate objects by two groups of four juvenile greater bushbabies (Otolemur garnettii) was examined in the laboratory. Substantial investigatory behavior was shown by all subjects. In the first study, subjects showed interest in a wide variety of nonfood stimulus objects. In the second, subjects displayed sustained interest in and investigation of non-food stimulus objects over three sessions. Bushbabies showed preferences for larger, more manipulable objects and variations in total contact over days. Individual differences were observed in the duration and types of contact with objects. These observations contradict earlier reports that prosimians show little interest in inanimate, non-food objects.  相似文献   
2.
The goal of our research was to study the effect of geomagnetic field (GMF) disturbances, in terms of K, Kp, Ak, Ap, and SK indices, on children's affective (emotional) and cognitive competence during different forms of organization of pretend play. We studied two forms of management of the playing process: 1) teacher‐directed frontal play with simultaneous involvement of all children in the classroom and 2) child‐directed play in various small groups. Twenty‐six observations were performed on 51 children in two mixed‐age classrooms. The mean age of the children was 4.6 years, with age span from 3 to 6 years. We found a significant increase in cognitive behavior during child‐directed play in groups compared with frontal, teacher‐directed management of the lesson. During child‐directed play children's behavior was negatively correlated with geomagnetic disturbance in both affective and cognitive domains (R = ? 0.47, p < 0.029, n = 21) as compared with teacher‐directed play where there was no significant interaction. We believe the dependence of the GMF effect on the type of the organization of the educational process is explained by the less‐stressful environment of the child‐directed playing conditions compared with teacher‐directed in which the directive role of the teacher can mask a possible GMF effect.  相似文献   
3.
Exposure to shiftwork has been associated with multiple health disorders and cognitive impairments in humans. We tested if we could replicate metabolic and cognitive consequences of shiftwork, as reported in humans, in a rat model comparable to 5 wks of non-rotating night shifts. The following hypotheses were addressed: (i) shiftwork enhances body-weight gain, which would indicate metabolic effects; and (ii) shiftwork negatively affects learning of a simple goal-directed behavior, i.e., the association of lever pressing with food reward (instrumental learning), which would indicate cognitive effects. We used a novel method of forced locomotion to model work during the animals' normal resting period. We first show that Wistar rats, indeed, are active throughout a shiftwork protocol. In contrast with previous findings, the shiftwork protocol attenuated the normal weight gain to 76?±?8?g in 5 wks as compared to 123?±?15?g in the control group. The discrepancy with previous work may be explained by the concurrent observation that with our shiftwork protocol rats did not adjust their between-work circadian activity pattern. They maintained a normal level of activity during the “off-work” periods. In the control experiment, rats were kept active during the dark period, normally dominated by activity. This demonstrated that forced activity, per se, did not affect body-weight gain (mean±SEM: 85?±?11?g over 5 wks as compared to 84?±?11?g in the control group). Rats were trained on an instrumental learning paradigm during the fifth week of the protocol. All groups showed equivalent increases in lever pressing from the first (3.8?±?.7) to the sixth (21.3?±?2.4) session, and needed a similar amount of sessions (5.1?±?.3) to reach a learning criterion (≥27 out of 30 lever presses). These results suggest that while on prolonged non-rotating shiftwork, not fully reversing the circadian rhythm might actually be beneficial to prevent body-weight gain and cognitive impairments. (Author correspondence: )  相似文献   
4.

Aims

The second most frequently reported post-treatment symptom in cancer survivors are concerns about impaired cognition. Despite numerous studies demonstrating significant impairments in a portion of survivors, information on effective treatments remains an emerging area of research. This study examined the effectiveness of a group-based cognitive rehabilitation intervention in cancer survivors.

Main methods

This study was a randomized, controlled study of a 7-week cognitive rehabilitation intervention delivered in group format. Participants were evaluated with subjective symptom questionnaires and objective neurocognitive tests prior to and following treatment.

Key findings

Twenty-eight participants (mean age 58 years) with a median of 3 years (± 6 years) post-primary/adjuvant treatment and various cancer sites (breast, bladder, prostate, colon, uterine) completed the study. Compared to baseline, the treatment group demonstrated improvements in symptoms of perceived cognitive impairments (p < .01), cognitive abilities (p < .01) and overall quality of life with regard to cognitive symptoms (p < .01) as measured by the FACT-Cog. The treatment group also improved on objective measures of attention (p < .05) and a trend toward improvement on verbal memory. Significant improvement was not observed on all cognitive tests.

Significance

A group based cognitive rehabilitation intervention in cancer survivors was effective for improving attention abilities and overall quality of life related to cognition. Results suggest that group based cognitive rehabilitation may be an effective intervention for treating cognitive dysfunction in cancer patients and should be further studied in a larger trial with an active control condition.  相似文献   
5.
本研究通过对雌雄子午沙鼠进行新物体识别和社会认知实验,运用免疫组化方法检测其相关脑区合成催产素(OT)、加压素(AVP)和多巴胺(DA)能的神经元数量,采用酶联免疫试验(ELISA)方法检测了其血清中OT、AVP的水平,探究了雌雄子午沙鼠的两性认知差异及其神经内分泌水平的差异。结果表明,雌雄子午沙鼠对新物体的探究时间均要显著高于旧物体,雌雄子午沙鼠的辨别指数无显著差异(P>0.05);雄性子午沙鼠随着探究次数的增加对重复刺激鼠a的探究时间不断减少,对陌生刺激鼠b的探究时间显著高于刺激鼠a(P<0.05);雌性子午沙鼠没有此趋势。雄性子午沙鼠OT能神经元数量在下丘脑室旁核(PVN)和视上核(SON)均要显著少于雌性(P<0.05);雄性个体DA能神经元数量在黑质显著高于雌性(P<0.01);然而雄性个体DA能神经元数量在腹侧被盖区显著少于雌性(P<0.01);雌雄子午沙鼠血清OT、AVP水平均无显著差异。综上所述,雌雄子午沙鼠对新物体的识别能力无显著差异,然而雄性子午沙鼠的社会认知能力强于雌性。在神经内分泌水平上,雌雄子午沙鼠PVN和SON中OT能神经元数量、黑质和腹侧背盖区的DA能神经元数量均呈现出了两性差异。  相似文献   
6.
Taller children tend to have better cognitive ability, and the relationship between height and cognition has been proposed as an explanation for the height-wage labor market premium. Height-cognition associations may arise due to social factors that favor taller individuals or be driven by “common factors” that are correlated with height and cognition. Indeed, there is now evidence of a genetic correlation between height and cognition that provides specific evidence for this concern. We examine whether genetic factors explain the relationship by estimating associations between childhood height and cognition in the Twins Early Development Study. We find that height is associated with better cognition even after controlling for genetic and environmental factors shared by twins. The association between height and cognition within fraternal twin pairs is also robust to controlling for individual genetic predictors of height and cognition. These results suggest that genetic factors are not solely responsible for driving the relationship between height and cognition.  相似文献   
7.
目的:应用事件相关电位技术探讨36 h完全睡眠剥夺对认知功能的影响。方法:9名健康被试参加36h睡眠剥夺试验,被试在36 h睡眠剥夺前后分别接受数字-符号联想测验,同时记录其事件相关电位,分析其在睡眠剥夺前后认知功能的动态变化情况。结果:1被试在睡眠剥夺前后的反应时相比[(748.16±193.27)与(775.79±205.48)ms],显著增加(t=3.86,P0.05),正确率相比[(74.56±0.11)与(67.12±0.07)],没有显著性差异(P0.05)。2被试在睡眠剥夺36 h后,P3、P4、C3和C4四点潜伏期没有显著性变化[P3:(296.44±16.61)与(300.22±16.16)ms,t=1.43,P=0.19;P4:(303.33±38.48)与(308.78±38.65)ms,t=2.35,P=0.05;C3:(309.56±34.09)与(308.44±28.49)ms,t=0.45,P=0.66;C4:(317.33±64.83)与(303.33±39.42)ms,t=1.31,P=0.23],四点波幅降低,且差异具有统计学意义(P0.05)[P3:(2.74±1.21)与(1.32±0.92)μv,t=2.54,P=0.04;P4:(2.34±1.27)与(0.94±0.49)μv,t=3.44,P=0.01;C3:(2.60±1.49)与(0.94±0.78)μv,t=2.65,P=0.03;C4:(2.60±0.81)与(1.11±1.03)μv,t=2.61,P=0.03]。结论:睡眠剥夺影响人的正常认知活动,损害了大脑对冲突信息的判断,睡眠对维持大脑的正常功能有重要作用。  相似文献   
8.
Numerous studies have emerged recently that demonstrate the possibility of modulating, and in some cases enhancing, cognitive processes by exciting brain regions involved in working memory and attention using transcranial electrical brain stimulation. Some researchers now believe the cerebellum supports cognition, possibly via a remote neuromodulatory effect on the prefrontal cortex. This paper describes a procedure for investigating a role for the cerebellum in cognition using transcranial direct current stimulation (tDCS), and a selection of information-processing tasks of varying task difficulty, which have previously been shown to involve working memory, attention and cerebellar functioning. One task is called the Paced Auditory Serial Addition Task (PASAT) and the other a novel variant of this task called the Paced Auditory Serial Subtraction Task (PASST). A verb generation task and its two controls (noun and verb reading) were also investigated. All five tasks were performed by three separate groups of participants, before and after the modulation of cortico-cerebellar connectivity using anodal, cathodal or sham tDCS over the right cerebellar cortex. The procedure demonstrates how performance (accuracy, verbal response latency and variability) could be selectively improved after cathodal stimulation, but only during tasks that the participants rated as difficult, and not easy. Performance was unchanged by anodal or sham stimulation. These findings demonstrate a role for the cerebellum in cognition, whereby activity in the left prefrontal cortex is likely dis-inhibited by cathodal tDCS over the right cerebellar cortex. Transcranial brain stimulation is growing in popularity in various labs and clinics. However, the after-effects of tDCS are inconsistent between individuals and not always polarity-specific, and may even be task- or load-specific, all of which requires further study. Future efforts might also be guided towards neuro-enhancement in cerebellar patients presenting with cognitive impairment once a better understanding of brain stimulation mechanisms has emerged.  相似文献   
9.
We investigated the possible influence of testosterone (T) on cognitive functioning in women with polycystic ovary syndrome (PCOS), an endocrine disorder associated with elevated levels of free testosterone (free T). Performance on a battery of neuropsychological tests in 29 women with elevated free T levels due to PCOS was compared to the performance of 22 age- and education-matched, healthy control women with free T levels in the normal female range. Women with PCOS had significantly higher levels of free T (estimated by the free androgen index) and demonstrated significantly worse performance on tests of verbal fluency, verbal memory, manual dexterity, and visuospatial working memory than the healthy control women. No differences between the groups were found on tests of mental rotation, spatial visualization, spatial perception, or perceptual speed. These results suggest that, in women, elevations in free T may be associated with poorer performance on cognitive tasks that tend to show a female advantage.  相似文献   
10.
In a previous study, we found that women with polycystic ovary syndrome (PCOS), an endocrine disorder characterized by chronic hyperandrogenism, performed more poorly than healthy, matched controls on a number of neuropsychological tests, in particular tests of verbal fluency, verbal memory, manual dexterity, and visuospatial working memory. This randomized, placebo-controlled trial was undertaken to investigate whether pharmacologic manipulation of free testosterone (free T) levels in women with PCOS might affect their performance on cognitive tests. Nineteen women with PCOS completed a battery of neuropsychological tests before and after 3 months of treatment with either an anti-androgen (cyproterone acetate) plus estrogen or with a placebo. Hormone treatment of women with PCOS caused a significant reduction in their free T levels but did not affect performance on tests visuospatial ability, verbal memory, manual dexterity, or perceptual speed. Women treated with hormone therapy did, however, demonstrate an improvement in their performance on a test of verbal fluency compared to their pre-treatment scores. These findings suggest that changes in free T levels do not have a significant impact on cognitive performance in women with PCOS, although reductions in free T may be beneficial for verbal fluency.  相似文献   
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